Java’s interface language feature confuses many Java newbies. Many mistakenly assume that interfaces only sidestep Java’s failure to support multiple implementation inheritance. In reality ...

Understanding the differences between an abstract class and interface is key to designing loosely coupled and extensible applications.

A controversial new proposal for .NET suggests the introduction of a limited form of multiple inheritance via abstract interfaces. This feature was inspired by Java’s default methods.

Neither of the two "big" programming languages to come out in the last few years, Java or C#, make use of multiple implementation inheritance, providing only interface inheritance.